rear rebuild, making sure I get all the required parts

[Zep5.0]

I believe urethane is all you'll be able to find. And since these don't directly touch the chassis there will be little NVH difference from the factory rubber.

 

[XR7-4.6]

And the beauty of urethane is you don’t need to tighten/torque the components in their resting at ride height position since they aren’t bonded to the sleeves like rubber bushings. Just make sure you lube them.

 

[KevinVarnes]

Are these available separately like the rest of the bushings? I can't seem to find them for sale outside of urethane kits.

As stated, I don't think you will be too disappointed with the urethane bushings. They aren't harsh, but more firm and controlled. It's hard to describe. If you notice any difference at all I think you will be pleased.